This invention relates to a coffee making machine which incorporates a coffee grinder from which the ground coffee is transferred to a filter placed in a filter carrier, a brewing water outlet positioned above the filter carrier and a plate (emplacement) for supporting a coffee-receiving receptacle underneath the filter carrier.
In household-type coffee making machines of conventional structure, a filter, placed in a filter carrier, is manually filled with ground coffee before the brewing process and the filter is positioned, in preparation for the brewing process, underneath a hot water outlet and above a coffee-receiving receptacle such as a coffee pot or a coffee cup. The filter carrier is in most cases so structured that it may be removed from the brewing position for the purpose of loading it with ground coffee and for removing the coffee grounds therefrom. Known types of filter carriers may be those which can be inserted from above, pivoted or pushed in.
Since pre-ground coffee, even if carefully stored, loses some of its aroma, coffee makers have become known which are coupled with a coffee grinder as a structural unit in such a manner that the ground coffee, obtained from coffee beans only immediately before the brewing process is, within the machine assembly, transported from the grinding mechanism to the filter, or parts of the coffee grinder itself form the filter. In structures which embody the first-named combination, coffee mills with cone or disk or roll grinding mechanisms are used. The ground coffee falls from the grinding mechanism into a receiving device and is advanced therefrom by means of a mechanical transporting device into a filter which is in the brewing position. In the above-noted second variant the grinding mechanism is positioned immediately above the filter situated in the brewing position and thus the ground coffee falls directly into the filter.
It is a common disadvantage of both solutions that the transporting device or the grinding mechanisms are exposed to the steam generated during the brewing process or the water condensate resulting therefrom. The components can be protected only by providing expensive seals or partitions.
In the embodiments in which the parts of the coffee grinder themselves form the filter, grinders with rapidly rotating impact blades are used. The bottom of the working chamber of the grinder is designed as a permanent filter and the ground coffee remains in the working chamber after the grinding process. Thereafter, the hot brewing water is guided into the working chamber over the ground coffee and flows through the permanent filter bottom into a receptacle, such as a coffee pot or a coffee cup. It is a disadvantage of this system that the structural elements of the impact grinder, that is, the working chamber, the impact blades, the seals, etc. are exposed to the brewing water and after the brewing process these components have to be cleaned of the coffee grounds externally of the machine. Further, because of the high dust proportion which is formed in a coffee ground by impact-blade grinders, the filtered coffee will not be of the best obtainable quality, particularly if permanent filters are used.